Illustrated Articles

Dogs + Parasites

  • The ear mite is a surface mite that lives on cats, dogs, rabbits, and ferrets. It is usually found in the ear canal but it can also live on the skin surface. Mites are barely visible to the naked eye. Clinical signs of infestation vary in severity and may include ear irritation, leading to scratching at the ears or head shaking, dark waxy or crusty discharge from the ear, areas of hair loss resulting from self-trauma, a crusted rash around or in the ear, and an aural hematoma. Your veterinarian will advise you about which insecticidal products are suitable. Your veterinarian may want to re-examine your pet to ensure that the mites have been eliminated after the initial treatment has been performed.

  • Echinococcus multilocularis is a tapeworm species that is found in the Northern Hemisphere. Dogs, cats, and humans are all susceptible to infection by E. multilocularis, along with additional species. While the parasite typically produces no clinical sign in cats, it can have life-threatening effects in humans. E. multilocularis is impossible to distinguish from other tapeworm species without specialized testing, but it responds to the same dewormers that are used to treat other tapeworm species. Therefore, pets suspected of having tapeworms should be treated promptly and care should be taken to avoid direct contact with animal feces.

  • Flea allergy dermatitis is a common cause of allergic reactions in dogs. The antigens in the flea saliva cause an intensely itchy response in sensitive dogs. Itching and hair loss in the region from the middle of the back to the tail base and down the rear legs (the flea triangle) is often associated with this allergy. Strict flea control is essential for treatment and prevention.

  • Fleas are the most common nuisance and parasite affecting dogs, and an infestation can lead to serious health problems. Flea control requires a three-pronged approach; they need to be eliminated from 1) your dog, 2) any other cats and dogs that you have, 3) your home and yard. There are many flea control products available and your veterinarian can help you determine which are the safest and most effective for your pets.

  • Fluralaner is given by mouth or applied topically and is used to treat flea and tick infestations, and also off-label to treat certain types of mange and mites. Give as directed. Side effects are uncommon but may include stomach upset or neurologic symptoms. Do not use in pets with a history of seizures. If a negative reaction occurs, please call the veterinary office.

  • Giardiasis is an intestinal infection caused by a microscopic protozoan. These parasites attach themselves to the intestinal wall, and the damage causes an acute, sudden onset of foul-smelling diarrhea. Diagnosis may be by routine fecal flotation or presumptively based on clinical signs. Fenbendazole and metronidazole are the drugs most commonly used to treat giardiasis.

  • Harvest mites, also known as red bugs, trombiculid mites, scrub-itch mites, berry bugs or, in their larval stage as chiggers, are mites that are commonly found in forests and grasslands. Harvest mites are relatives of spiders. They are nearly microscopic measuring only 1/100 of an inch (0.4 mm) and have an orange hue. A common species of Harvest mite in Northern America is Trombicula alfreddugesi.  

  • Heartworm disease is a serious and potentially fatal disease. It is caused by a blood-borne parasite known as Dirofilaria immitis. Adult heartworms may live up to five years and, during this time, the female produces millions of offspring called microfilaria. You can prevent your dog from getting heartworms by using a heartworm preventive.

  • Heartworm disease is serious and potentially life-threatening to dogs. Treatment involves several components to combat potential bacterial infection, kill the heartworm larvae (microfilaria), kill the adult heartworms, and then test to confirm successful treatment. Complete rest for a dog undergoing treatment is essential. The prognosis for dogs after heartworm treatment is generally good if the pet owner follows all veterinary recommendations closely.

  • Hepatozoonosis in dogs is caused by ingestion of one of two organisms: H. americanum and H. canis. Both parasites are more common in the southern United States. The clinical sign and treatments for dogs with hepatozoonosis differ depending on the parasite species causing the infection. In either case, with appropriate treatment, the prognosis is generally good.